On Tue, 31 Jan 2023 16:38:47 +0000 Jonathan Cameron via <[email protected]> wrote:
> From: Gregory Price <[email protected]> > > This commit enables each CXL Type-3 device to contain one volatile > memory region and one persistent region. > > Two new properties have been added to cxl-type3 device initialization: > [volatile-memdev] and [persistent-memdev] > > The existing [memdev] property has been deprecated and will default the > memory region to a persistent memory region (although a user may assign > the region to a ram or file backed region). It cannot be used in > combination with the new [persistent-memdev] property. > > Partitioning volatile memory from persistent memory is not yet supported. > > Volatile memory is mapped at DPA(0x0), while Persistent memory is mapped > at DPA(vmem->size), per CXL Spec 8.2.9.8.2.0 - Get Partition Info. > > Signed-off-by: Gregory Price <[email protected]> > Signed-off-by: Jonathan Cameron <[email protected]> > Hi Gregory, I've added support for multiple HDM decoders and hence can now test both volatile and non volatile on same device. It very nearly all works. With one exception which is I couldn't poke the first byte of the non volatile region. I think we have an off by one in a single check. Interestingly it makes no difference when creating an FS on top (which was my standard test) so I only noticed when poking memory addresses directly to sanity check the HDM decoder setup. I'll roll a v2 if no one shouts out that I'm wrong. Note that adding multiple HDM decoders massively increases the number of test cases over what we had before to poke all the corners so I may well be missing stuff. Hopefully can send an RFC of that support out next week. Jonathan > -MemTxResult cxl_type3_read(PCIDevice *d, hwaddr host_addr, uint64_t *data, > - unsigned size, MemTxAttrs attrs) > +static int cxl_type3_hpa_to_as_and_dpa(CXLType3Dev *ct3d, > + hwaddr host_addr, > + unsigned int size, > + AddressSpace **as, > + uint64_t *dpa_offset) > { > - CXLType3Dev *ct3d = CXL_TYPE3(d); > - uint64_t dpa_offset; > - MemoryRegion *mr; > + MemoryRegion *vmr = NULL, *pmr = NULL; > > - /* TODO support volatile region */ > - mr = host_memory_backend_get_memory(ct3d->hostmem); > - if (!mr) { > - return MEMTX_ERROR; > + if (ct3d->hostvmem) { > + vmr = host_memory_backend_get_memory(ct3d->hostvmem); > + } > + if (ct3d->hostpmem) { > + pmr = host_memory_backend_get_memory(ct3d->hostpmem); > } > > - if (!cxl_type3_dpa(ct3d, host_addr, &dpa_offset)) { > - return MEMTX_ERROR; > + if (!vmr && !pmr) { > + return -ENODEV; > + } > + > + if (!cxl_type3_dpa(ct3d, host_addr, dpa_offset)) { > + return -EINVAL; > + } > + > + if (*dpa_offset > int128_get64(ct3d->cxl_dstate.mem_size)) { > + return -EINVAL; > + } > + > + if (vmr) { > + if (*dpa_offset <= int128_get64(vmr->size)) { Off by one I think. < > + *as = &ct3d->hostvmem_as; > + } else { > + *as = &ct3d->hostpmem_as; > + *dpa_offset -= vmr->size; > + } > + } else { > + *as = &ct3d->hostpmem_as; > } > > - if (dpa_offset > int128_get64(mr->size)) { > + return 0; > +}
